In the art of the internal combustion engine (ICE), a device is typically needed to mix air and fuel, the mixture of which is then delivered to the ICE's combustion chamber. This mixture is usually delivered toward the end of the ICE's compression stroke, and then ignited using, for example, a spark plug. In the past, this mixing and delivering was achieved through the use of a carburetor. Over more recent years however, fuel injectors have increasingly replaced the carburetor as the preferred means to deliver fuel to the ICE's combustion chamber. (See generally U.S. Pat. No. 3,430,616 to Glöckler)
A fuel injector vaporizes (atomizes) fuel by pumping it in controlled amounts and under high force through a nozzle (spray tip). Fuel injector components typically include a plunger covering a valve opening. In many instances, the plunger is retracted upon activation of an electronic valve solenoid. This allows pressurized fuel to flow into an atomizer and out of a spray tip. Once the valve solenoid is deactivated, a valve spring returns the plunger to its at-rest position covering the valve opening. Timing the activation of the valve solenoid is controlled by various controllers in the art such as an engine control unit (ECU), a control area network (CAN), and the like. Precise control of the valve opening allows for precise metering of fuel. Fuel injectors provide for easier starting of an ICE as well as increased fuel efficiency and potentially cleaner exhaust emissions because the fuel is metered into the combustion chamber with improved precision and accuracy.
Cleaner emissions can be further improved for an ICE by passing its exhaust emissions through a device known as a catalytic converter. Since exhaust emissions are fairly consistent and predictable, the catalytic converter can convert some of the more toxic emissions to less toxic substances by way of catalyzed chemical reactions. A typical catalytic converter for a gasoline (petro) fueled ICE in a vehicle is a “three way” converter. This type of converter converts the main pollutants in automobile exhaust, namely carbon monoxide (CO), hydrocarbons (unburned fuel) (CxHx) and oxides of nitrogen (NOx). The catalytic converter coverts, by a reduction reaction, nitrogen oxides back to nitrogen (i.e., 2NOx→xO2+N2). The carbon monoxide components are oxidized to carbon dioxide (i.e., 2CO+O2→2CO2. The un-burnt hydrocarbons are oxidized to carbon dioxide and water (i.e., CxH2x+2+[(3x+1)/2]O2→xCO2+(x+1)H2O).
Despite these recent advances in the art, improvement in fuel efficiency and in the reduction if emissions of ICEs are possible and desired.